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alfik |
////////////////////////////////////////////////////////////////////////
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// $Id: iret.cc 11106 2012-03-25 11:54:32Z sshwarts $
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/////////////////////////////////////////////////////////////////////////
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//
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// Copyright (c) 2005-2012 Stanislav Shwartsman
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// Written by Stanislav Shwartsman [sshwarts at sourceforge net]
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//
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// This library is free software; you can redistribute it and/or
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// modify it under the terms of the GNU Lesser General Public
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// License as published by the Free Software Foundation; either
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// version 2 of the License, or (at your option) any later version.
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//
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// This library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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// Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public
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// License along with this library; if not, write to the Free Software
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// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA B 02110-1301 USA
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//
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/////////////////////////////////////////////////////////////////////////
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#define NEED_CPU_REG_SHORTCUTS 1
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#include "bochs.h"
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#include "cpu.h"
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#define LOG_THIS BX_CPU_THIS_PTR
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void BX_CPP_AttrRegparmN(1)
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BX_CPU_C::iret_protected(bxInstruction_c *i)
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{
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Bit16u raw_cs_selector, raw_ss_selector;
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bx_selector_t cs_selector, ss_selector;
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Bit32u dword1, dword2;
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bx_descriptor_t cs_descriptor, ss_descriptor;
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#if BX_SUPPORT_X86_64
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if (long_mode()) {
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long_iret(i);
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return;
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}
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#endif
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if (BX_CPU_THIS_PTR get_NT()) /* NT = 1: RETURN FROM NESTED TASK */
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{
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/* what's the deal with NT & VM ? */
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Bit16u raw_link_selector;
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bx_selector_t link_selector;
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bx_descriptor_t tss_descriptor;
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if (BX_CPU_THIS_PTR get_VM())
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BX_PANIC(("iret_protected: VM sholdn't be set here !"));
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BX_DEBUG(("IRET: nested task return"));
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if (BX_CPU_THIS_PTR tr.cache.valid==0)
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BX_PANIC(("IRET: TR not valid"));
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// examine back link selector in TSS addressed by current TR
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raw_link_selector = system_read_word(BX_CPU_THIS_PTR tr.cache.u.segment.base);
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// must specify global, else #TS(new TSS selector)
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parse_selector(raw_link_selector, &link_selector);
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if (link_selector.ti) {
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BX_ERROR(("iret: link selector.ti=1"));
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exception(BX_TS_EXCEPTION, raw_link_selector & 0xfffc);
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}
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// index must be within GDT limits, else #TS(new TSS selector)
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fetch_raw_descriptor(&link_selector, &dword1, &dword2, BX_TS_EXCEPTION);
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// AR byte must specify TSS, else #TS(new TSS selector)
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// new TSS must be busy, else #TS(new TSS selector)
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parse_descriptor(dword1, dword2, &tss_descriptor);
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if (tss_descriptor.valid==0 || tss_descriptor.segment) {
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BX_ERROR(("iret: TSS selector points to bad TSS"));
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exception(BX_TS_EXCEPTION, raw_link_selector & 0xfffc);
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}
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if (tss_descriptor.type != BX_SYS_SEGMENT_BUSY_286_TSS &&
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tss_descriptor.type != BX_SYS_SEGMENT_BUSY_386_TSS)
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{
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BX_ERROR(("iret: TSS selector points to bad TSS"));
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exception(BX_TS_EXCEPTION, raw_link_selector & 0xfffc);
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}
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// TSS must be present, else #NP(new TSS selector)
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if (! IS_PRESENT(tss_descriptor)) {
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BX_ERROR(("iret: task descriptor.p == 0"));
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exception(BX_NP_EXCEPTION, raw_link_selector & 0xfffc);
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}
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// switch tasks (without nesting) to TSS specified by back link selector
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task_switch(i, &link_selector, &tss_descriptor,
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BX_TASK_FROM_IRET, dword1, dword2);
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return;
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}
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/* NT = 0: INTERRUPT RETURN ON STACK -or STACK_RETURN_TO_V86 */
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unsigned top_nbytes_same;
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Bit32u new_eip = 0, new_esp, temp_ESP, new_eflags = 0;
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Bit16u new_ip = 0, new_flags = 0;
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/* 16bit opsize | 32bit opsize
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* ==============================
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* SS eSP+8 | SS eSP+16
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* SP eSP+6 | ESP eSP+12
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* -------------------------------
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* FLAGS eSP+4 | EFLAGS eSP+8
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* CS eSP+2 | CS eSP+4
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* IP eSP+0 | EIP eSP+0
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*/
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if (i->os32L()) {
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top_nbytes_same = 12;
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}
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else {
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top_nbytes_same = 6;
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}
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if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b)
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temp_ESP = ESP;
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else
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temp_ESP = SP;
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if (i->os32L()) {
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new_eflags = stack_read_dword(temp_ESP + 8);
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raw_cs_selector = (Bit16u) stack_read_dword(temp_ESP + 4);
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new_eip = stack_read_dword(temp_ESP + 0);
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// if VM=1 in flags image on stack then STACK_RETURN_TO_V86
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if (new_eflags & EFlagsVMMask) {
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if (CPL == 0) {
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stack_return_to_v86(new_eip, raw_cs_selector, new_eflags);
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return;
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}
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else BX_INFO(("iret: VM set on stack, CPL!=0"));
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}
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}
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else {
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new_flags = stack_read_word(temp_ESP + 4);
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raw_cs_selector = stack_read_word(temp_ESP + 2);
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new_ip = stack_read_word(temp_ESP + 0);
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}
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parse_selector(raw_cs_selector, &cs_selector);
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// return CS selector must be non-null, else #GP(0)
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if ((raw_cs_selector & 0xfffc) == 0) {
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BX_ERROR(("iret: return CS selector null"));
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exception(BX_GP_EXCEPTION, 0);
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}
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// selector index must be within descriptor table limits,
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// else #GP(return selector)
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fetch_raw_descriptor(&cs_selector, &dword1, &dword2, BX_GP_EXCEPTION);
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parse_descriptor(dword1, dword2, &cs_descriptor);
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// return CS selector RPL must be >= CPL, else #GP(return selector)
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if (cs_selector.rpl < CPL) {
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BX_ERROR(("iret: return selector RPL < CPL"));
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exception(BX_GP_EXCEPTION, raw_cs_selector & 0xfffc);
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}
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// check code-segment descriptor
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check_cs(&cs_descriptor, raw_cs_selector, 0, cs_selector.rpl);
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if (cs_selector.rpl == CPL) { /* INTERRUPT RETURN TO SAME LEVEL */
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/* top 6/12 bytes on stack must be within limits, else #SS(0) */
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/* satisfied above */
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if (i->os32L()) {
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/* load CS-cache with new code segment descriptor */
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branch_far32(&cs_selector, &cs_descriptor, new_eip, cs_selector.rpl);
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// ID,VIP,VIF,AC,VM,RF,x,NT,IOPL,OF,DF,IF,TF,SF,ZF,x,AF,x,PF,x,CF
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Bit32u changeMask = EFlagsOSZAPCMask | EFlagsTFMask |
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EFlagsDFMask | EFlagsNTMask | EFlagsRFMask;
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#if BX_CPU_LEVEL >= 4
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changeMask |= (EFlagsIDMask | EFlagsACMask); // ID/AC
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#endif
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if (CPL <= BX_CPU_THIS_PTR get_IOPL())
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changeMask |= EFlagsIFMask;
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if (CPL == 0)
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changeMask |= EFlagsVIPMask | EFlagsVIFMask | EFlagsIOPLMask;
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// IF only changed if (CPL <= EFLAGS.IOPL)
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// VIF, VIP, IOPL only changed if CPL == 0
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// VM unaffected
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writeEFlags(new_eflags, changeMask);
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}
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else {
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/* load CS-cache with new code segment descriptor */
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branch_far32(&cs_selector, &cs_descriptor, (Bit32u) new_ip, cs_selector.rpl);
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/* load flags with third word on stack */
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write_flags(new_flags, CPL==0, CPL<=BX_CPU_THIS_PTR get_IOPL());
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}
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/* increment stack by 6/12 */
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if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b)
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ESP += top_nbytes_same;
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else
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SP += top_nbytes_same;
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return;
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}
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else { /* INTERRUPT RETURN TO OUTER PRIVILEGE LEVEL */
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/* 16bit opsize | 32bit opsize
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* ==============================
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* SS eSP+8 | SS eSP+16
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* SP eSP+6 | ESP eSP+12
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* FLAGS eSP+4 | EFLAGS eSP+8
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| 213 |
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* CS eSP+2 | CS eSP+4
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* IP eSP+0 | EIP eSP+0
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*/
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| 216 |
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| 217 |
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/* examine return SS selector and associated descriptor */
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| 218 |
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if (i->os32L()) {
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raw_ss_selector = stack_read_word(temp_ESP + 16);
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| 220 |
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}
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| 221 |
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else {
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| 222 |
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raw_ss_selector = stack_read_word(temp_ESP + 8);
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| 223 |
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}
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| 224 |
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| 225 |
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/* selector must be non-null, else #GP(0) */
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| 226 |
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if ((raw_ss_selector & 0xfffc) == 0) {
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| 227 |
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BX_ERROR(("iret: SS selector null"));
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| 228 |
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exception(BX_GP_EXCEPTION, 0);
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| 229 |
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}
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| 230 |
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| 231 |
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parse_selector(raw_ss_selector, &ss_selector);
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| 232 |
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| 233 |
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/* selector RPL must = RPL of return CS selector,
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| 234 |
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* else #GP(SS selector) */
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| 235 |
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if (ss_selector.rpl != cs_selector.rpl) {
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| 236 |
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BX_ERROR(("iret: SS.rpl != CS.rpl"));
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| 237 |
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exception(BX_GP_EXCEPTION, raw_ss_selector & 0xfffc);
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| 238 |
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}
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| 239 |
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| 240 |
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/* selector index must be within its descriptor table limits,
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| 241 |
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* else #GP(SS selector) */
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| 242 |
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fetch_raw_descriptor(&ss_selector, &dword1, &dword2, BX_GP_EXCEPTION);
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| 243 |
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| 244 |
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parse_descriptor(dword1, dword2, &ss_descriptor);
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| 245 |
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| 246 |
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/* AR byte must indicate a writable data segment,
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| 247 |
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* else #GP(SS selector) */
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| 248 |
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if (ss_descriptor.valid==0 || ss_descriptor.segment==0 ||
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| 249 |
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IS_CODE_SEGMENT(ss_descriptor.type) ||
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| 250 |
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!IS_DATA_SEGMENT_WRITEABLE(ss_descriptor.type))
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| 251 |
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{
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| 252 |
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BX_ERROR(("iret: SS AR byte not writable or code segment"));
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| 253 |
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exception(BX_GP_EXCEPTION, raw_ss_selector & 0xfffc);
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| 254 |
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}
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| 255 |
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| 256 |
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/* stack segment DPL must equal the RPL of the return CS selector,
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| 257 |
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* else #GP(SS selector) */
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| 258 |
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if (ss_descriptor.dpl != cs_selector.rpl) {
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| 259 |
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BX_ERROR(("iret: SS.dpl != CS selector RPL"));
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| 260 |
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exception(BX_GP_EXCEPTION, raw_ss_selector & 0xfffc);
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| 261 |
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}
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| 262 |
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| 263 |
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/* SS must be present, else #NP(SS selector) */
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| 264 |
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if (! IS_PRESENT(ss_descriptor)) {
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| 265 |
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BX_ERROR(("iret: SS not present!"));
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| 266 |
|
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exception(BX_NP_EXCEPTION, raw_ss_selector & 0xfffc);
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| 267 |
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}
|
| 268 |
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| 269 |
|
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if (i->os32L()) {
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| 270 |
|
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new_esp = stack_read_dword(temp_ESP + 12);
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| 271 |
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new_eflags = stack_read_dword(temp_ESP + 8);
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| 272 |
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new_eip = stack_read_dword(temp_ESP + 0);
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| 273 |
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}
|
| 274 |
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else {
|
| 275 |
|
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new_esp = stack_read_word(temp_ESP + 6);
|
| 276 |
|
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new_eflags = stack_read_word(temp_ESP + 4);
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| 277 |
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new_eip = stack_read_word(temp_ESP + 0);
|
| 278 |
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}
|
| 279 |
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| 280 |
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// ID,VIP,VIF,AC,VM,RF,x,NT,IOPL,OF,DF,IF,TF,SF,ZF,x,AF,x,PF,x,CF
|
| 281 |
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Bit32u changeMask = EFlagsOSZAPCMask | EFlagsTFMask |
|
| 282 |
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EFlagsDFMask | EFlagsNTMask | EFlagsRFMask;
|
| 283 |
|
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#if BX_CPU_LEVEL >= 4
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| 284 |
|
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changeMask |= (EFlagsIDMask | EFlagsACMask); // ID/AC
|
| 285 |
|
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#endif
|
| 286 |
|
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if (CPL <= BX_CPU_THIS_PTR get_IOPL())
|
| 287 |
|
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changeMask |= EFlagsIFMask;
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| 288 |
|
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if (CPL == 0)
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| 289 |
|
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changeMask |= EFlagsVIPMask | EFlagsVIFMask | EFlagsIOPLMask;
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| 290 |
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| 291 |
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if (! i->os32L()) // 16 bit
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| 292 |
|
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changeMask &= 0xffff;
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| 293 |
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| 294 |
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/* load CS:EIP from stack */
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| 295 |
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/* load the CS-cache with CS descriptor */
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| 296 |
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/* set CPL to the RPL of the return CS selector */
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| 297 |
|
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branch_far32(&cs_selector, &cs_descriptor, new_eip, cs_selector.rpl);
|
| 298 |
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| 299 |
|
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// IF only changed if (prev_CPL <= EFLAGS.IOPL)
|
| 300 |
|
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// VIF, VIP, IOPL only changed if prev_CPL == 0
|
| 301 |
|
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// VM unaffected
|
| 302 |
|
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writeEFlags(new_eflags, changeMask);
|
| 303 |
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| 304 |
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// load SS:eSP from stack
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| 305 |
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// load the SS-cache with SS descriptor
|
| 306 |
|
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load_ss(&ss_selector, &ss_descriptor, cs_selector.rpl);
|
| 307 |
|
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if (ss_descriptor.u.segment.d_b)
|
| 308 |
|
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ESP = new_esp;
|
| 309 |
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else
|
| 310 |
|
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SP = new_esp;
|
| 311 |
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| 312 |
|
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validate_seg_regs();
|
| 313 |
|
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}
|
| 314 |
|
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}
|
| 315 |
|
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| 316 |
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#if BX_SUPPORT_X86_64
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| 317 |
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void BX_CPP_AttrRegparmN(1)
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| 318 |
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BX_CPU_C::long_iret(bxInstruction_c *i)
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| 319 |
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{
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| 320 |
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Bit16u raw_cs_selector, raw_ss_selector;
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bx_selector_t cs_selector, ss_selector;
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Bit32u dword1, dword2;
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bx_descriptor_t cs_descriptor, ss_descriptor;
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Bit32u new_eflags;
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Bit64u new_rip, new_rsp, temp_RSP;
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BX_DEBUG (("LONG MODE IRET"));
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if (BX_CPU_THIS_PTR get_NT()) {
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BX_ERROR(("iret64: return from nested task in x86-64 mode !"));
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exception(BX_GP_EXCEPTION, 0);
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}
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/* 64bit opsize
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* ============
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* SS eSP+32
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* ESP eSP+24
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* -------------
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* EFLAGS eSP+16
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* CS eSP+8
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* EIP eSP+0
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*/
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if (long64_mode()) temp_RSP = RSP;
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else {
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if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b) temp_RSP = ESP;
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else temp_RSP = SP;
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}
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unsigned top_nbytes_same = 0; /* stop compiler warnings */
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#if BX_SUPPORT_X86_64
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if (i->os64L()) {
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new_eflags = (Bit32u) stack_read_qword(temp_RSP + 16);
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raw_cs_selector = (Bit16u) stack_read_qword(temp_RSP + 8);
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new_rip = stack_read_qword(temp_RSP + 0);
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top_nbytes_same = 24;
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}
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else
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#endif
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| 361 |
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if (i->os32L()) {
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| 362 |
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new_eflags = stack_read_dword(temp_RSP + 8);
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| 363 |
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raw_cs_selector = (Bit16u) stack_read_dword(temp_RSP + 4);
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new_rip = (Bit64u) stack_read_dword(temp_RSP + 0);
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top_nbytes_same = 12;
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}
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else {
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new_eflags = stack_read_word(temp_RSP + 4);
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raw_cs_selector = stack_read_word(temp_RSP + 2);
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new_rip = (Bit64u) stack_read_word(temp_RSP + 0);
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top_nbytes_same = 6;
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}
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// ignore VM flag in long mode
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new_eflags &= ~EFlagsVMMask;
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parse_selector(raw_cs_selector, &cs_selector);
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// return CS selector must be non-null, else #GP(0)
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if ((raw_cs_selector & 0xfffc) == 0) {
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BX_ERROR(("iret64: return CS selector null"));
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exception(BX_GP_EXCEPTION, 0);
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}
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// selector index must be within descriptor table limits,
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// else #GP(return selector)
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fetch_raw_descriptor(&cs_selector, &dword1, &dword2, BX_GP_EXCEPTION);
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parse_descriptor(dword1, dword2, &cs_descriptor);
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// return CS selector RPL must be >= CPL, else #GP(return selector)
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if (cs_selector.rpl < CPL) {
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BX_ERROR(("iret64: return selector RPL < CPL"));
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exception(BX_GP_EXCEPTION, raw_cs_selector & 0xfffc);
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}
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// check code-segment descriptor
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check_cs(&cs_descriptor, raw_cs_selector, 0, cs_selector.rpl);
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/* INTERRUPT RETURN TO SAME PRIVILEGE LEVEL */
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if (cs_selector.rpl == CPL && !i->os64L())
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{
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/* top 24 bytes on stack must be within limits, else #SS(0) */
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/* satisfied above */
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| 404 |
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| 405 |
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/* load CS:EIP from stack */
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/* load CS-cache with new code segment descriptor */
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if(cs_descriptor.u.segment.l) {
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branch_far64(&cs_selector, &cs_descriptor, new_rip, CPL);
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}
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else {
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| 411 |
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branch_far32(&cs_selector, &cs_descriptor, (Bit32u) new_rip, CPL);
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}
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// ID,VIP,VIF,AC,VM,RF,x,NT,IOPL,OF,DF,IF,TF,SF,ZF,x,AF,x,PF,x,CF
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Bit32u changeMask = EFlagsOSZAPCMask | EFlagsTFMask | EFlagsDFMask |
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EFlagsNTMask | EFlagsRFMask | EFlagsIDMask | EFlagsACMask;
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if (CPL <= BX_CPU_THIS_PTR get_IOPL())
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changeMask |= EFlagsIFMask;
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if (CPL == 0)
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| 420 |
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changeMask |= EFlagsVIPMask | EFlagsVIFMask | EFlagsIOPLMask;
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| 421 |
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| 422 |
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if (! i->os32L()) // 16 bit
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changeMask &= 0xffff;
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| 425 |
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// IF only changed if (CPL <= EFLAGS.IOPL)
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// VIF, VIP, IOPL only changed if CPL == 0
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// VM unaffected
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| 428 |
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writeEFlags(new_eflags, changeMask);
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| 429 |
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| 430 |
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/* we are NOT in 64-bit mode */
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if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b)
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| 432 |
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ESP += top_nbytes_same;
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else
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SP += top_nbytes_same;
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| 435 |
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}
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| 436 |
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else { /* INTERRUPT RETURN TO OUTER PRIVILEGE LEVEL or 64 BIT MODE */
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| 437 |
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/* 64bit opsize
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| 438 |
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* ============
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| 439 |
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* SS eSP+32
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| 440 |
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* ESP eSP+24
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| 441 |
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* EFLAGS eSP+16
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| 442 |
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* CS eSP+8
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| 443 |
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* EIP eSP+0
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| 444 |
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*/
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| 445 |
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| 446 |
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/* examine return SS selector and associated descriptor */
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| 447 |
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#if BX_SUPPORT_X86_64
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| 448 |
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if (i->os64L()) {
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| 449 |
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raw_ss_selector = (Bit16u) stack_read_qword(temp_RSP + 32);
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| 450 |
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new_rsp = stack_read_qword(temp_RSP + 24);
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| 451 |
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}
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| 452 |
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else
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| 453 |
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#endif
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| 454 |
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{
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| 455 |
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if (i->os32L()) {
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| 456 |
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raw_ss_selector = (Bit16u) stack_read_dword(temp_RSP + 16);
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| 457 |
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new_rsp = (Bit64u) stack_read_dword(temp_RSP + 12);
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| 458 |
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}
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| 459 |
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else {
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| 460 |
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raw_ss_selector = stack_read_word(temp_RSP + 8);
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| 461 |
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new_rsp = (Bit64u) stack_read_word(temp_RSP + 6);
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| 462 |
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}
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| 463 |
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}
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| 464 |
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| 465 |
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if ((raw_ss_selector & 0xfffc) == 0) {
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| 466 |
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if (! IS_LONG64_SEGMENT(cs_descriptor) || cs_selector.rpl == 3) {
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| 467 |
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BX_ERROR(("iret64: SS selector null"));
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| 468 |
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exception(BX_GP_EXCEPTION, 0);
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| 469 |
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}
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| 470 |
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}
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| 471 |
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else {
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| 472 |
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parse_selector(raw_ss_selector, &ss_selector);
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| 473 |
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| 474 |
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/* selector RPL must = RPL of return CS selector,
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| 475 |
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* else #GP(SS selector) */
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| 476 |
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if (ss_selector.rpl != cs_selector.rpl) {
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| 477 |
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BX_ERROR(("iret64: SS.rpl != CS.rpl"));
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| 478 |
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exception(BX_GP_EXCEPTION, raw_ss_selector & 0xfffc);
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| 479 |
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}
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| 480 |
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| 481 |
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/* selector index must be within its descriptor table limits,
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| 482 |
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* else #GP(SS selector) */
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| 483 |
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fetch_raw_descriptor(&ss_selector, &dword1, &dword2, BX_GP_EXCEPTION);
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| 484 |
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parse_descriptor(dword1, dword2, &ss_descriptor);
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| 485 |
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| 486 |
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/* AR byte must indicate a writable data segment,
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| 487 |
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* else #GP(SS selector) */
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| 488 |
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if (ss_descriptor.valid==0 || ss_descriptor.segment==0 ||
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| 489 |
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IS_CODE_SEGMENT(ss_descriptor.type) ||
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| 490 |
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!IS_DATA_SEGMENT_WRITEABLE(ss_descriptor.type))
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| 491 |
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{
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| 492 |
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BX_ERROR(("iret64: SS AR byte not writable or code segment"));
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| 493 |
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exception(BX_GP_EXCEPTION, raw_ss_selector & 0xfffc);
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| 494 |
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}
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| 495 |
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| 496 |
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/* stack segment DPL must equal the RPL of the return CS selector,
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| 497 |
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* else #GP(SS selector) */
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| 498 |
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if (ss_descriptor.dpl != cs_selector.rpl) {
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| 499 |
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BX_ERROR(("iret64: SS.dpl != CS selector RPL"));
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| 500 |
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exception(BX_GP_EXCEPTION, raw_ss_selector & 0xfffc);
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| 501 |
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}
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| 502 |
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| 503 |
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/* SS must be present, else #NP(SS selector) */
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| 504 |
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if (! IS_PRESENT(ss_descriptor)) {
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| 505 |
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BX_ERROR(("iret64: SS not present!"));
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| 506 |
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exception(BX_NP_EXCEPTION, raw_ss_selector & 0xfffc);
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| 507 |
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}
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| 508 |
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}
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| 509 |
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| 510 |
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Bit8u prev_cpl = CPL; /* previous CPL */
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| 511 |
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| 512 |
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// ID,VIP,VIF,AC,VM,RF,x,NT,IOPL,OF,DF,IF,TF,SF,ZF,x,AF,x,PF,x,CF
|
| 513 |
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Bit32u changeMask = EFlagsOSZAPCMask | EFlagsTFMask | EFlagsDFMask |
|
| 514 |
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EFlagsNTMask | EFlagsRFMask | EFlagsIDMask | EFlagsACMask;
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| 515 |
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if (prev_cpl <= BX_CPU_THIS_PTR get_IOPL())
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| 516 |
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changeMask |= EFlagsIFMask;
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| 517 |
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if (prev_cpl == 0)
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| 518 |
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changeMask |= EFlagsVIPMask | EFlagsVIFMask | EFlagsIOPLMask;
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| 519 |
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| 520 |
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if (! i->os32L()) // 16 bit
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| 521 |
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changeMask &= 0xffff;
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| 522 |
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| 523 |
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/* set CPL to the RPL of the return CS selector */
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| 524 |
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branch_far64(&cs_selector, &cs_descriptor, new_rip, cs_selector.rpl);
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| 525 |
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| 526 |
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// IF only changed if (prev_CPL <= EFLAGS.IOPL)
|
| 527 |
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// VIF, VIP, IOPL only changed if prev_CPL == 0
|
| 528 |
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// VM unaffected
|
| 529 |
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writeEFlags(new_eflags, changeMask);
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| 530 |
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| 531 |
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if ((raw_ss_selector & 0xfffc) != 0) {
|
| 532 |
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// load SS:RSP from stack
|
| 533 |
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// load the SS-cache with SS descriptor
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| 534 |
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load_ss(&ss_selector, &ss_descriptor, cs_selector.rpl);
|
| 535 |
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}
|
| 536 |
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else {
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| 537 |
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// we are in 64-bit mode !
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| 538 |
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load_null_selector(&BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS], raw_ss_selector);
|
| 539 |
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}
|
| 540 |
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| 541 |
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if (long64_mode()) RSP = new_rsp;
|
| 542 |
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else {
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| 543 |
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if (ss_descriptor.u.segment.d_b) ESP = (Bit32u) new_rsp;
|
| 544 |
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else SP = (Bit16u) new_rsp;
|
| 545 |
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}
|
| 546 |
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| 547 |
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if (prev_cpl != CPL) validate_seg_regs();
|
| 548 |
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}
|
| 549 |
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}
|
| 550 |
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#endif
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